Documentation
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Overview ¶
Package reflectutil has an arbitrary assortment of helpers for dealing with protobuf reflection including:
- `Path` for describing paths within proto Messages.
- `MapRangeSorted` for deterministically iterating over proto Maps.
- `ShallowCopy` to safely make shallow copies of messages.
Index ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func MapRangeSorted ¶
func MapRangeSorted(m protoreflect.Map, keyKind protoreflect.Kind, cb func(protoreflect.MapKey, protoreflect.Value) bool)
MapRangeSorted is the same as `m.Range()` except that it iterates through the map in sorted order.
The keys AND values of the map are snapshotted before your callback runs; This means that addition or removal of keys from the map will not be reflected to your callback. Interior modification of values (i.e. Value.field = something) MAY be reflected, but wholesale re-assignment of map value will not be reflected.
Note that for the purposes of this function and proto reflection in general, Int32Kind==Int64Kind and Uint32Kind==Uint64Kind; Providing Int32Kind for a map with an int64 key is not an issue (and vice versa).
func ShallowCopy ¶
ShallowCopy returns a new, shallow copy of `msg`.
This is a safe alterative to the "obvious" implementation:
tmp := *underlyingMsgValue return &tmp
Unfortunately, protobuf holds many internal structures which are unsafe to shallow copy, and `go vet` has been hinted to complain about this.
If `msg` is invalid (typically a nil *SomeMessage), this returns `msg` as-is.
This implementation also copies unknown fields.
Types ¶
type Path ¶
type Path []PathItem
Path is a series of tokens to indicate some (possibly nested) field within a Message.
type PathField ¶
type PathField struct{ protoreflect.FieldDescriptor }
PathField is a PathItem which indicates field access in a Message.
func (PathField) Retrieve ¶
func (f PathField) Retrieve(v protoreflect.Value) (ret protoreflect.Value)
Retrieve implements PathItem
type PathItem ¶
type PathItem interface {
fmt.Stringer
// Retrieve applies this PathItem to the given Value.
//
// If it fails, returns a Value where v.IsValid() == false.
Retrieve(protoreflect.Value) protoreflect.Value
}
PathItem is a single step in a Path.
func MustMakePathItem ¶
MustMakePathItem will return a PathItem from `item` or panic.
`item` can be a:
- int (PathListIdx)
- protoreflect.FieldDescriptor (PathField)
- protoreflect.MapKey (PathMapKey)
type PathListIdx ¶
type PathListIdx int
PathListIdx is a PathItem which indicates the indexing of a repeated field.
func (PathListIdx) Retrieve ¶
func (i PathListIdx) Retrieve(v protoreflect.Value) (ret protoreflect.Value)
Retrieve implements PathItem
func (PathListIdx) String ¶
func (i PathListIdx) String() string
String implements fmt.Stringer.
This makes the most sense when used with Path.String(); this formats as `[index_value]`.
type PathMapKey ¶
type PathMapKey protoreflect.MapKey
PathMapKey is a PathItem which indicates the indexing of a map field.
func (PathMapKey) Retrieve ¶
func (k PathMapKey) Retrieve(v protoreflect.Value) (ret protoreflect.Value)
Retrieve implements PathItem
func (PathMapKey) String ¶
func (k PathMapKey) String() string
String implements fmt.Stringer.
This makes the most sense when used with Path.String(); this formats as `[map_key]` for integer/bool types, and `["map_key"]` for string types.
Source Files